linden518
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Moving Coil Step-Up Transformer for Denon 103?
Jan Vigne
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Step up transformers do what the name implies, they step up the voltage from one level at the input to a higher level at the output. They are passive devices so no active circuit noise or distortion is added by the transformer. They are probably the cleanest way to step up the voltage of a cartridge but have limitations in that they are typically fixed in the amount of gain they provide and have a fixed input impedance. If you run several cartridges and require the ability to trim levels and input impedance/capacitance, then you should use an active device with those provisions. In most cases - and certainly for the Denon 103 - the transformer would be my first choice in a step up device. You might even find the Denon transformers on the used market for a good price. You would then run the transformer into a moving magent phono input. You would not require an outboard active phono stage if you use the transformer. If you're considering the 103, I would also consider the Zu cartridge recently reviewed in Stereophile.

linden518
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Jan, thanks so much for your explanation. Much clearer now! I did read that article for the Zu 103 cartridge & I'd probably opt for that cartridge, as it seems like a relative bargain.

I have another question, though. Among the standalone phono stages, are there models optimized specifically for low-output MC? I saw that most of them accommodate MM or high-output MC... thanks again.

Jan Vigne
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"Optimized"? 'Splain "optimized", keemosabee.

linden518
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Quote:
"Optimized"? 'Splain "optimized", keemosabee.


Well, phono stages that are geared specifically for LOMC rather than HOMC/MM. Since I don't have a phono stage in my Leben system, I'd like to see if I can just get a quality phono stage that's specifically for LOMC rather than getting a phono stage + step-up...

Jan Vigne
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Yes, there are phono pre amps that favor low output mc's though most are meant to work within a range of output voltages from the cartridge. Check the Stereophile review archives to determine what features you wish to purchase. Keep in mind higher gain from a dedicated LOMC phono stage will probably have more noise that a MM phono stage with a step up transformer.

linden518
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Quote:
Keep in mind higher gain from a dedicated LOMC phono stage will probably have more noise that a MM phono stage with a step up transformer.


D'oh! Why do you have to do that to me!

But seriously, if you have any recommendation for a quiet LOMC phono stage, pls let me know... thnx.

Elk
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I can suggest the Musical Surroundings Phonomena

# Discrete transistor topology
# Class A operation
# Dual mono audio layout
# Super matched pair of low noise input transistors
# Adjustable gain: 40 - 60 dB in 16 steps
# Adjustable loading: 30 ohms - 100 k-ohms in 128 steps
# Adjustable capacitance

It is clean, clear, detailed and quiet, "affordable" (always a relative term) at $600.00 list.

There also is a battery power supply option.

60 dB of gain is sufficient, although even more clean gain is nice with low output cartridges. This gets expensive.

linden518
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Thanks, Elk. I'll check out Phonomena, but honestly, I'm leaning towards MM right now, most likely with Clearaudio Virtuoso Wood cartridge. Just too much right now to set up for LOMC (money-wise & planning-wise); I'll probably come back to LOMC later, well after I set up my turntable first.

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